I am actually pretty surprised that my battery "lasted" almost 5 years. It finally could not hold a charge for a start after a week of sitting with no load. The polar vortices that brought days of -10F temperature may have helped finally killed the battery.
In retrospect, after installing the new battery, I came to realized that original battery had been at below ~70% capability for most of its life beyond probably 1 year. Let me explain. Even after a full overnight trickle charge the OEM battery would start the GT-R just fine, but the starting would be somewhat sluggish, almost as though the starter was not sufficient to crank the engine over. This behavior, to me became normal over time, but it was not until the new battery was installed that I realized how snappy the GT-R startup can actually be. So to those on stock GT-R battery, I urge you do a simple voltmeter test.
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| Topping off new battery. |
I did not want to spend $50-60 to get a battery testing kit, considering that a new battery would be double that at about $100-120. I am not a battery expert, but I do have an EE background. So, I did some battery reading and found that low temperature does affect charge, but not as much as say when overall charge capacity is reduced. A healthy battery can survive at -50F (the freezing point of that concentration of sulphuric acid). As the battery charge holding capacity reduces, the freezing point increases very quickly!
